This application is based on and incorporates herein by reference Japanese Patent Application No. 2001-122825 filed on Apr. 20, 2001 and Japanese Patent Application No. 2001-247322 filed on Aug. 16, 2001.
1. Field of the Invention
The present invention relates to a wiper arm having a cover for covering at least part of an arm head of the wiper arm, at which the wiper arm is connected to a pivot shaft.
2. Description of Related Art
A securing portion of a base end portion (also referred to as an arm head) of a wiper arm is connected to a pivot shaft, for example, by installing and tightening a nut onto a threaded portion of a distal end of the pivot shaft received through the securing portion of the base end portion of the wiper arm. The securing portion of the wiper arm is covered with a cover (cap) to achieve an improved appearance of the wiper and/or to restrain penetration of water into the securing portion (e.g., penetration of the water to the pivot shaft).
The wiper arm having the cover for covering the securing portion is disclosed, for example, in Japanese Unexamined Patent Publication No. 2000-95070 and Japanese Unexamined Patent Publication No. 8-72676.
Japanese unexamined Patent Publication No. 2000-95070 discloses a wiper arm provided with a detachable cover. In this wiper arm, the cover partially covers a minimum required portion of the securing portion. At time of maintenance work or the like, the cover is removed from the base end portion. Furthermore, when the wiper arm is shipped from a wiper manufacturer to an automobile manufacturer, the cover is connected to the base end portion. Thus, in the automobile manufacturer, when the wiper arm is connected to a vehicle body (pivot shaft), the cover is first removed from the based end portion of the wiper arm. After the wiper arm is connected to the vehicle body (pivot shaft), the cover needs to be connected to the base end portion once again, resulting in the tedious time consuming assembling operation. Furthermore, the removed cover can be lost during the assembling operation, causing an interruption of the assembling operation.
Japanese Unexamined Patent Publication No. 8-72676 discloses a wiper arm provided with a cover, which covers most of a base end portion of the wiper arm including lateral walls of the base end portion. In this wiper arm, although a size of the cover is larger than the cover disclosed in Japanese unexamined Patent Publication No. 2000-95070, the cover is hingedly connected to the base end portion in a manner that allows closing and opening of the securing portion of the base end portion by the cover without detachment of the cover from the base end portion. However, when the cover is placed in the open state, the cover is only hingedly connected to the base end portion, so that the cover can be easily rotated by relatively small vibrations and loads, causing unintentional closing movement of the cover. Thus, in the connecting operation of the wiper arm to the vehicle (pivot shaft), the cover often interferes with the connecting operation.
Furthermore, after the wiper arm is connected to the vehicle (pivot shaft), the cover needs to be securely closed against the securing portion of the base end portion. To achieve this, an engaging piece and an engaging groove are provided in the cover and the base end portion, respectively, to engage with each other when the cover is closed against the securing portion. The engaging piece and the engaging groove are also engaged with each other to prevent unintentional rotation (opening) of the cover and damage of the cover by vibrations or the like when the wiper arm is shipped or is transported (for example, for the purpose of product delivery). Thus, before the wiper arm is connected to the vehicle (pivot shaft), the engaging claw and the engaging groove need to be disengaged from each other to open the cover, causing the tedious time consuming assembling operation.
The present invention addresses the above disadvantages. Thus, it is an objective of the present invention to provide a wiper arm, which can achieve an improved appearance of the wiper arm and can accelerate a connecting operation of an arm head of the wiper arm to a pivot shaft.
To achieve the objective of the present invention, there is provided a wiper arm including an arm head, which is securely connected to a pivot shaft, a cover, which is connected to the arm head for covering at least part of the arm head and is rotatable in a closing direction and an opening direction about a rotational axis thereof between a fully closed position and a fully opened position relative to the arm head, and an intermediate position holding means for restraining rotation of the cover in both the closing direction and the opening direction at at least one intermediate position between the fully opened position and the fully closed position.
The intermediate position holding means may include at least one holding projection and at least one holding hole. The at least one holding projection is provided in one of the cover and the arm head. The at least one holding hole is provided in the other of the cover and the arm head and is engageable with a corresponding one of the at least one holding projection.
Alternatively, the intermediate position holding means may include at least one holding projection, at least one first engaging protrusion and at least one second engaging protrusion. The at least one holding projection protrudes from the cover and is resiliently engaged with an outer wall surface of the arm head to restrain the rotation of the cover when the cover is rotated in the closing direction. The at least one first engaging protrusion is provided in the other of the cover and the arm head and protrudes from a corresponding one of the hinge projections. The at least one second engaging protrusion is provided in the one of the cover and the arm head and is located adjacent to a corresponding one of the hinge holes.
The wiper arm may further includes a fully opened position holding means for restraining the rotation of the cover in the closing direction at the fully opened position. The fully opened position holding means may include the at least one first engaging protrusion, the at least one second engaging protrusion and at least one opening movement limiting end. The at least one opening movement limiting end is provided in the one of the cover and the arm head and is located adjacent to a corresponding one of the hinge holes, wherein when the cover is positioned in the fully opened position, each first engaging protrusion abuts against a corresponding one of the at least one opening movement limiting end and is held between the corresponding one of the at least one second engaging protrusion and the corresponding one of the at least one opening movement limiting end.